Perspective Therapeutics, Inc. ("Perspective" or the "Company") (NYSE AMERICAN: CATX), a radiopharmaceutical company pioneering advanced treatments for cancers throughout the body, announced today that the first patient was treated with [212Pb]PSV359 in a Phase 1/2a dose-finding trial to determine safety and preliminary anti-tumor activity of the radiopharmaceutical [212Pb]PSV359 in patients with solid tumors that express fibroblast activation protein alpha (FAP-α). Patients are being selected for [212Pb]PSV359 targeted alpha particle therapy by SPECT imaging with [203Pb]PSV359.
"We are excited to explore a new avenue to treat cancers expressing FAP-α with [212Pb]PSV359," commented Markus Puhlmann, Chief Medical Officer of Perspective. "FAP-α is expressed directly on certain tumors as well as on cells that form the stroma, a part of the tumor microenvironment, which also plays a role in disease progression and treatment outcome in additional solid tumors. This study aims to select a dose for [212Pb]PSV359 to advance as either a monotherapy or eventually in combination with other agents for future clinical development."
"PSV359 showcases the capabilities of our discovery team in creating novel radiopharmaceuticals to provide innovative therapies for cancer patients in need of new treatment options," said Thijs Spoor, Chief Executive Officer of Perspective. "There has been an extensive development history of FAP-α directed cancer diagnostics and therapeutics. When we selected PSV359 to advance into the clinic, we optimized the construct for preferential uptake and retention in the tumor, in addition to binding affinity to FAP-α and fast clearance from healthy tissues. We look forward to seeing how these characteristics translate into the clinic, and applying these design principles to future constructs to advance into clinical development."
About PSV359
PSV359 was designed to target and deliver 212Pb to tumor sites expressing fibroblast activation protein-α, or FAP-α, associated with multiple highly prevalent solid tumors, with patients in need of additional treatment options. The targeting moiety may also be radiolabeled with 203Pb or 68Ga (known as PSV377) to detect FAP-α expression in individual patients. Preclinical imaging and therapy as well as human imaging results suggest Perspective's proprietary targeting ligand has improved levels of target engagement and uptake in tumors, as well as reduced retention in healthy tissues, which may result in a desirable therapeutic index.
Perspective is conducting a multi-center, open-label, dose-finding and dose-expansion study (clinicaltrials.gov identifier NCT06710756) of [212Pb]PSV359 in patients with advanced solid tumors that express FAP-α as determined by imaging with [203Pb]PSV359. The primary objective of the dose finding phase of the study is to assess the safety and tolerability of various doses of [212Pb]PSV359 in order to determine the recommended Phase 2 dose to be used in the expansion phase of the study, where anti-tumor activities may be an additional primary outcome measure.
About FAP-α
FAP-α is a protein abundantly expressed on the surface of cancer-associated fibroblasts (CAFs) in the stroma, a part of the tumor microenvironment (TME) in the majority of epithelial cancers. In addition to expression on CAFs, FAP-α is expressed on certain cancer cells themselves, including sarcomas and mesotheliomas.1,2,3,4 Higher FAP-α expression has been found to be associated with poor prognosis in a number of solid tumors such as colorectal cancer, pancreatic cancer, stomach cancer, mesothelioma, head and neck cancer, esophageal cancer, and ovarian cancer.5,6,7,8,9 Expression of FAP-α in healthy tissues is usually low.3,4
About Perspective Therapeutics, Inc.
Perspective Therapeutics, Inc. is a radiopharmaceutical company pioneering advanced treatments for cancers throughout the body. The Company has proprietary technology that utilizes the alpha-emitting isotope 212Pb to deliver powerful radiation specifically to cancer cells via specialized targeting moieties. The Company is also developing complementary imaging diagnostics that incorporate the same targeting moieties, which provide the opportunity to personalize treatment and optimize patient outcomes. This "theranostic" approach enables the ability to see the specific tumor and then treat it to potentially improve efficacy and minimize toxicity.
The Company's melanoma (VMT01), neuroendocrine tumor (VMT-α-NET), and solid tumor (PSV359) programs are in Phase 1/2a imaging and therapy trials in the U.S. The Company is growing its regional network of drug product finishing facilities, enabled by its proprietary 212Pb generator, to deliver patient-ready products for clinical trials and commercial operations.
For more information, please visit the Company's website at www.perspectivetherapeutics.com.